my 1999 chevy lumana overheated-shut it off and now it wont turn over

Look under the hood in the fuse box. See if you find a relay that says ASD, or Auto Shut Down. That's the one that shut off your car.

sorry Im so slow getting back to your answer,Mark,I do appreciate your help..Im still having trouble but I checked it out closer and I dont have any power anywhere,powerwindows,dash,etc. Dome light works plus the headlights work I checked all the fuses under the hood and inside the car,all o.k. Dont know what to check next?

Sounds like you have a BCM problem. Body Control Module. May want to hit a salvage yard or check Ebay. When you have multiple failures like that, it's usually the BCM. The car should still turn over. Have you tested your neutral safety switch? Try holding the key to the ON position and move the shifter from Park to N and D. See if it will fire up. If you have anti theft, that may be playing a factor with the BCM. Just to see if the engine will turn over, you can touch the contacts together on the starter and it should turn over. Like in this video: https://www.youtube.com/watch?v=fpPOcO6f798

you could have seized your motor when it over heated